In the usual aerosol container, product and propellant are placed in a valved container. The aerosol valve includes a valve stem which emerges through the pedestal portion of the container closure or mounting cup. An actuator is frictionally fitted to the valve stem; the actuator being the component that receives manual pressure from the user of the aerosol container to actuate or open the valve and, thereby, to cause egress of the container contents. Actuators are often of the type referred to as aerosol button actuators. Examples of such button actuators are set forth in U.S. Pat. Nos. 4,463,784; 3,122,180; 3,319,669 and 4,915,266. Actuator buttons generally come in two sizes, a normal size wherein the circumference of the button on the stem is substantially the same or slightly larger than the circumference of the pedestal portion of the mounting cup. A second size is an enlarged button actuator wherein the circumference of the bottom of the actuator extends considerably beyond the circumference of the pedestal portion.
In a normal size actuator button, it is common to dispose the actuator on the valve stem before crimping the valve to the pedestal portion of the mounting cup. In the instance of an enlarged actuator button, the button cannot be disposed on the valve stem prior to crimping the valve to the pedestal for reason that the enlarged diameter of the base of the actuator forecloses positioning the crimping tools within the well of the mounting cup defined by the pedestal and the body of the mounting cup.
There are two principal methods for filling an aerosol container with propellant, namely, the "under-the-cup" and "pressure filling."
More and more, the aerosol industry is resorting to "pressure filling" of the container with propellant rather than "under the cup" filling. The reasons are to diminish the loss of costly propellants and to minimize emission of propellant into the atmosphere. In under-the-cup filling, a filling head actually lifts the mounting cup partially out of the mouth of the aerosol container and the propellant is driven under pressure through the opening between the bead (opening) of the container and the channel or circular skirt of the mounting cup; the clinching of the mounting cup and the bead of the container being accomplished in the same operation after completion of the propellant filling.
With pressure filling of the propellant, the valve and its associated mounting cup are affixed to the container in a sealed relationship prior to the introduction of the propellant to the container. Pressure filling is accomplished by having a filling head advance against the peripheral flange on the actuator button which depresses the button so that the bottom of the button seals against the pedestal portion of the mounting cup, that is, the raised portion of the mounting cup through which the valve stem of the aerosol valve extends. The propellant enters the container around the stem and through the opening in the pedestal. With certain valves, the pressure of the propellant compresses the valve gasket and the principal filling route of the propellant is over the compressed gasket and down through castellated slots in the valve housing which surround the valve stem/valve body. Also, depending on the size of the orifice openings in the valve stem, there is propellant filling through the valve stem orifices, the valve stem being depressed to move the stem orifices into communication with the interior of the container.
Heretofore, in the instance where an enlarged aerosol actuator button has been utilized, the practice has been to clinch a valve bearing mounting cup to the container, then pressure fill the container with the enlarged actuator removed from the valve stem and subsequently assemble the enlarged actuator on the valve stem.
In the course of assembling the enlarged actuator to the valve stem, and particularly in the instance where the valve is an aerosol tilt valve, there is the opportunity for premature discharge of container contents. Thus, it is desirable to place the enlarged actuator button on the valve stem prior to filling the container with propellant.
It is an object of this invention to provide a method for the propellant filling of a valved aerosol container with an enlarged actuator in place on the valved aerosol container prior to filling the container with propellant.
It is a further object of this invention to provide an actuator button suitable for carrying out the method of this invention.